Ok let's get the horse out again. Today, I came across the situation shown in the photos below.

The green screw I know is used in main disconnect panels to get the neutral bar bonded to the cabinet. However, this was used as a subpanel. I don't think the screw is supposed to be there but it looks like it isn't fully in place so it may not actually be doing anything. Am I off the mark on that?

In the first picture you can see they did install a third grounding bar directly to the cabinet. The screw, if not fully in place, would then let the neutral float but I don't know that for sure and I was NOT going to stick a screw driver in there to see if it was tight or not.

So I am recommending that a Lic. and Qual. Electrician remove it or say it is ok. This is new construction and I am guessing that someone just forgot to pull the screw out completely.

FYI, The first picture is the lower portion of the panel. The second is a close up of the screw in question.

I will be working on the report tonight so if someone sees this and I need a good smack on the back of the head please reply. Subpanels are one thing I rarely see so I generally have to check my books and compare that to my pictures to make sure all it ok.

I agree with your take on the panel, the bonding screw looks like it has been backed out far enough so that it has no potential to the enclosure, but I would also prefer to see it not there at all (just incase someone decides to tighten it up). also this is not wrong but looks odd, why did they not just remove the neutral bus bond and use that as the grounding bus with a bond to the enclosure, that is more normal practice.

Was this installed by an electrician or a "gifted amature"?

Regards

Gerry

"To realize our true destiny, we must be guided not by a myth from our past, but by a vision of our future."

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jtedesco1 is a non-member guest and is in no way affiliated with InterNACHI or its members.

Re: Subpanel Bonding Screw

Andrew:

The green screw is the "main bonding jumper" to be used and installed in the main service disconnecting means. It should not be left in that panel because someone else taught in another world would probably screw it in and the attached image of your picture shows me that there is not a proper fitting and looks like whoever did that work was not familiar with the construction and operation of electrical equipment.

I may be wrong, but the panel looks like it is upside down??

Sure wish I could see more, so that I can help you cite more problems if any? I will be in Texas soon, and it is my understanding that they have been licensing electricians there for a while now, that's good but if this is the type of work they do there I would be weary??

We install panels upside down all the time.....most general service enclosures today can be installed either way. The panel shown here is fine to be installed upside down....perfectly safe and fine.

Among the other issues already stated....I would also note the neutral if it is # 6 AWG or smaller...would need to be continuous white or gray outer finish or by three continuous white stripes on the other than green insulation anong its entire length.

Paul W. Abernathy

“Promise me you'll always remember: You're braver than you believe, and stronger than you seem, and smarter than you think.” -RIP Dad, Love You!.10/10/2014

Disclaimer - All my posts on this forum are of my own personal opinion and in no way represent the opinions of Encore Wire, or other associations, organizations or affiliations.

Please Note:
Greg Fretwell is a non-member guest and is in no way affiliated with InterNACHI or its members.

Re: Subpanel Bonding Screw

This is why the electrician should put these things in their pocket when they are not dictated to be installed. I bet someone just stuck it in there later because they found it and didn't know what else to do with it. Take it out and throw it away.
Since all the breakers in the panel seem to go sideways I don't think there is a top or bottom. This is only important when you have up/down action on a breaker. Up "shall" be on. It is an ugly entrance on that raceway for the feeder.

I agree with Gerry's initial comments. Seems more logicaal to have removed the bonding jumper between the factory installed bus bars, bonded the left bar to the panel with the intended green bonding screw, run the grounds to the left bar, and the neutrals to the right bus bar.

I guess there is more than one way to skin a cat, as they say.

I have checked for continuity between the neutral bus and the panel in the past, though it is WAY beyond the SOP. I also agree that if the intent is to NOT use the bonding screw, it should have been removed at the time the panel was installed.